A multi-way directional valve is a combination valve with two or more directional spool valves as a main body. The product may be widely used in various engineering machine, agricultural machine and mining machine. A multi-way directional valve controls at least two actuator elements, and since different actuator elements require different work flows, while an oil source is allocated according to the maximum flow requirement, then if only one actuator element operates or the actuator elements operate at a low speed, redundant oil liquid has to be discharged at a high pressure, which results in loss of functions, excessive heat generation, which is extremely disadvantageous to life of a system and an element. In recent years, people impose higher and higher requirements on energy saving, and impose gradually higher requirements on energy saving and environmental protection of a hydraulic system.
Currently, at home or abroad, a forklift truck of 5 to 10 tons has a large flow requirement when lifting and a relative small flow requirement when inclining or when other attachments operate. However, a forklift truck of 5 to 10 tons generally applies a quantitative system which includes a manually operated multi-way directional valve equipped with two gear pumps. Two pumps cooperate to produce a combined flow of oil when a lifting operation is performed, and when inclining operation is performed or when other attachments operate, since a very small quantity of oil is required, the redundant oil source supplied by a quantitative pump is generally discharged at a pressure set by a safety valve, and as a result, a generator works at an idle speed and is susceptible to be powered off due to a too small torque. So, excepting a simple structure and a low cost, the wasted energy is huge, the manually operated multi-way directional valve requires a great operating force, a large shock in redirecting is generated, and a poor controlling performance is generated, having. However, with the development of science and technology and higher and higher requirements by people, the manually-operated valve can not meet the requirements of people; in addition, it is hard for the above solution to be implemented if a precise inching requirement is imposed on the actuator mechanism.